Optimizing power management chips to embrace the new era of automotive electrification

With the continuous development of the automotive industry and the rapid iteration of technology, automotive electrification has become the main trend of future development. As a core component of automotive electrification, power management chips are playing an increasingly important role. The market size is gradually expanding and showing a strong growth momentum. In order to cope with the changing market demand for electrification, the power management chip industry is constantly launching more efficient, safe and miniaturized products. WT Technology, a world-leading authorized agent of electronic components, has been deeply involved in the field of battery management for many years and has rich market experience and technical accumulation. Here we recommend an advanced power management chip from ADI.

Kenty Luo, senior technical support engineer at WT, said that with the help of cutting-edge technologies such as automotive electrification, digital cockpits, networks, and connectivity, ADI's solutions have helped achieve safer transportation, a more feature-rich cockpit experience, and more efficient electric vehicle performance. The system-level design and intelligent power management capabilities provided by ADI enable flexible and scalable platform solutions, and continue to innovate in precision detection, edge processing, software, and wireless technology to obtain real-time technical insights, and are committed to redefining the way value is created and delivered throughout the automotive ecosystem. Kenty introduced the four key elements of "high performance, functional safety, collaborative development, small size + low cost" and recommended related devices.

high performance

High efficiency is one of the key indicators of automotive electrification systems. Power management chips need to efficiently convert electrical energy and minimize energy loss, thereby improving the energy utilization of the entire system. High-performance power management chips can achieve high-efficiency conversion under different workloads, helping to reduce energy loss and improve overall component efficiency.

The first major advantage of high performance of automotive power chips is that they can reduce power consumption as much as possible. This is because the development of automotive electrification has spawned a large number of entertainment functions, which require very low static power consumption. Therefore, the design goal of power management chips is to reduce static current as much as possible to extend battery life and extend the standby time of the device; at the same time, the chip is also required to have lower power noise.

The MAX25232 is a small synchronous step-down converter with integrated high-side and low-side switches that can deliver up to 3A of current over an input voltage range of 3.5V to 36V while consuming only 3.5µA of quiescent current at no load. Over the normal 6V to 18V operating input range, the device provides ±2% output voltage accuracy in FPWM mode.

The converter has an ultra-short on-time capability of 65ns, which provides a large input-to-output conversion ratio. The voltage quality can be monitored by observing the PGOOD signal. The device can operate in a low dropout voltage at 99% duty cycle, making it ideal for automotive and industrial applications. The MAX25232 is also available in two fixed output voltages: 5V and 3.3V.

In addition, the device can be configured for 1V to 10V output voltage using an external resistor divider. The frequency is internally fixed at 2.1MHz, which reduces the number of external components while reducing output ripple and ensuring there is no AM interference. At the same time, a 400kHz option is also provided to minimize switching losses and improve efficiency.

The MAX25232 version uses a small (3mm x 3mm), 12-pin, TDFN package with an exposed pad and requires very few external components. It automatically enters skip mode at light loads, has an ultra-low quiescent current of 3.5µA at no load, and has spread spectrum modulation capability to minimize electromagnetic radiation caused by the modulation frequency. All performance is better than competing products.

Functional Safety

In addition to ensuring the electrical characteristics of automotive power products, ADI products also have the advantage of functional safety. With the continuous development of new energy vehicles, people are paying more and more attention to safety while paying attention to high performance, which is another major requirement for automotive power functional modules.

ADI has the ability to develop ASIL-D power product solutions and has a dedicated team to design and develop functional safety chips based on the ISO26262 standard. It also has an independent quality team that can perform functional safety assessments at specified stages according to ISO26262, and has mature and dedicated functional safety development procedures and safety plans.

After designing the power safety chip, ADI can provide customers with a safety manual and review FMEDA, hazard analysis, safety concepts, etc. with customers to better place the functional safety chip in the entire system. It can also work with partners to define functional safety requirements and develop interface protocols/DIA, etc.

ASIL (Automotive Safety Integrity Level) is the automotive safety integrity level. The latest ISO 26262 standard is a functional safety standard for road vehicles developed based on the characteristics of safety-related electrical and electronic systems and based on IEC 61508 "Functional safety of safety-related electrical/electronic/programmable electronic systems". This standard provides an ASIL-compliant framework for the development of automotive products.

ISO 26262 is the first functional safety standard in history applicable to mass-produced products. It only targets safety-related electrical and electronic systems, including motors, electronics and software parts, and is not applicable to non-electrical and electronic systems such as mechanical and hydraulic systems.

ADI's power products designed specifically for automobiles cover automotive cockpit electronics and infotainment systems, vehicle autonomous driving and safety, automotive LED drivers, and electrification systems such as battery management and powertrain, ensuring compliance with the ASIL framework. Based on market performance, Shijian strongly recommends the industry's only automotive-grade, ASIL-D power system detector, the MAX20480.

The MAX20480 is a complete ASIL-compliant SoC power system monitor with up to 7 voltage monitoring inputs. Each input has a programmable OV/UV threshold between 2.5% and 10% with an accuracy of ±1%. Two of the inputs have independent remote ground sense inputs and support DVS through an integrated I2C interface.

The MAX20480 includes a programmable flexible power-sequence recorder (FPSR). This recorder independently stores power-up and power-down time stamps to support on/off and sleep/standby power sequencing. The device includes both a programmable challenge/response watchdog, accessible through the I²C interface, and a programmable active-low RESET output.

Compared with independent ICs or discrete components, the MAX20480 can significantly reduce system size and component count while improving reliability. When used with a monitoring controller, the MAX20480 meets ASIL-D reliability standards. The device operates in an ambient temperature range of -40°C to +125°C. Application scenarios include unmanned driving systems, power system monitoring, and MCU/SoC monitoring.

Collaborative Development

Different car brands and models may have different requirements for power management, especially in terms of power requirements, protection functions, communication interfaces, etc. ADI cooperates with SoC manufacturers, Tier 1 suppliers and OEMs to design and develop power products based on the requirements of manufacturers, so as to better understand the customized needs of customers and tailor products that meet specific requirements to meet customer needs and provide better solutions.

The development of automobile electrification has led to the popularization of driverless driving. Autonomous driving has higher and higher requirements for computing power, which also means that the power requirements will become higher and higher. Kenty introduced that the MAX20411 is an automotive-grade SoC step-down power chip that ADI has developed based on market development trends and cooperation with manufacturers. It meets the ASIL-D standard and can provide an output current of up to 40A.

The MAX20411 is a family of high-efficiency, synchronous step-down converters that operate from a 3.0V to 5.5V input voltage range and provide an output voltage range of 0.5V to 1.275V. The wide input/output voltage range and up to 40A peak output current make it ideal for point-of-load and post-regulation. The output error is as low as ±0.75% over the entire load, supply, and temperature range.

The MAX20411 features a 2.1MHz fixed-frequency PWM mode for better noise immunity and load transient response. The 2.1MHz operating frequency allows the use of all-ceramic capacitors, minimizing external components. A spread-spectrum modulation option minimizes electromagnetic radiation. The integrated low RDS(ON)(ON) switch greatly improves efficiency at heavy loads and simplifies circuit layout compared to discrete solutions.

The device uses the MAXQ™ power architecture to provide high-precision transient performance and phase margin, allowing maximum power, performance, and accuracy while minimizing system cost for any particular application. It uses factory-preset output voltages (see the selection guide), and the I2C interface provides dynamic voltage regulation with programmable slew rate. Other features include programmable soft start and overtemperature protection for automotive ADAS systems and SoC core power supplies.